1. Field of the Invention
The disclosure relates to a multiphase flowmeter which can measure a flow quantity of multiphase fluid.
Priorities are claimed on Japanese Patent Application No. 2014-038733, filed Feb. 28, 2014, and Japanese Patent Application No. 2014-164930, filed Aug. 13, 2014, the contents of which are incorporated herein by reference.
2. Description of Related Art
In a case where a multiphase fluid in which water, oil, and gas are mixed flows in a pipe line, a multiphase flowmeter can measure a flow quantity of each fluid mixed in the multiphase fluid. Recently, various types of multiphase flowmeters are developed.
In Japanese Unexamined Patent Application Publication No. H08-271309, two multiphase density meters are described. Specifically, the two multiphase density meters are disposed on a horizontal pipe line along a flow direction of the multiphase fluid, and ratio of each fluid is calculated based on relative permittivity of the multiphase fluid. Time required for fluid to flow between the two multiphase density meters is calculated, and the flow quantity of the multiphase fluid is measured based on a correlation method.
In Japanese Unexamined Patent Application Publication No. H10-281843, a multiphase flowmeter is described. Specifically, the multiphase flowmeter is equipped with an electromagnetic flowmeter, a component ratio sensor, and a calculation circuit. The electromagnetic flowmeter and the component ratio sensor are disposed on a pipe line along a flow direction of the multiphase fluid. The calculation circuit calculates a flow quantity of each fluid mixed in the multiphase fluid based on measurement signals transmitted from the electromagnetic flowmeter and the component ratio sensor.
However, because the detection devices are combined in the multiphase flowmeter, the configuration of the entire multiphase flowmeter is complicated, and costs of the device are increased.